Geometric design instrument



Jan. 17, E967 D. v. swam GEOMETRIC DESIGN INSTRUMENT Filed Oct. 25, 1965@5 mnrm HHH II IIIHI mlym 2Q' INVENTQR United States Patent O 3,298,104GEOMETRIC DESIGN INSTRUMENT Dan Vernon Smith, 210-03 43rd St., Bayside,N.Y. 11361 Filed Oct. 23, 1965, Ser. No. 503,458 1 Claim. (cl. .s3- 27)This invention relates to geometric scribing machines and in particularto devices for moving a pen, pencil, stylus, cutting element or othersuitable marker for scribing a great variety of patterns havingrepeating curves of selectively varying radii. Such devices canadvantageously be employed as educational toys for children. i Geometricscribing machines which are useful as toys have been known in the priorart. However, they have generally had the inherent disadvantages ofcomplexity, of difliculty of manufacture, of producing limited varietyof patterns, of requiring drawing paper of special shapes and/or ofsusceptibility to damage when handled and used by children. Thisinvention is directed to avoiding the shortcomings of such prior artdevices.

An object of the invention is to provide an improved geometric scribingmachine having improved -capacity for providing a great Variety of-patterns by simple adjustments which determine the change of patterns.

Another object of the invention is to provide an irnproved geometricscribing machine which is simple to manufacture and is capable ofwithstanding rough and abusive handling by children.

Another object of the invention is to provide an improved geometricscribing machine consisting of five major components, each of which canbe manufactured in mass production as molded plastic parts.

Another object of the invention is to eliminate belts and the like inthe driving transmission of the components of the device so as to avoidfaulty patterns caused by slippage f the various rotating parts relativeto each Other.

Still another object of the invention is to .provide an improvedgeometric scribing machine having only intermeshing gear teeth fordriving all rotating elements.

j According to the invention there is provided a geometric scribingmachine which comprises a base member; a rotatable table -having gearteeth integral therewith along its periphery and pivoted to the basemember, such rotatable table having a recess in a central portionthereof adopted to receive a rectangular sheet of paper; means securingt-he four corners of the sheet of paper to the rotatable table; a handrotatable member having gear teeth integral therewith along itsperiphery and pivotably mounted to the base with its gear teeth inintermes-hing relationship with the gear teeth on `the rotatable table;a pattern' changing member pivoted to the base member and having gearteeth integral therewith which intermesh with the gear teeth on therotatable table; a plurality of guide pins extending upwardly from thebase member and spaced from each other along a curve, such patternchanging member having a plurality of radially spaced apertures in aplurality of radial patterns; and a bar member having a longitudinalslot at one end thereof which is engageable with a selected one of theplurality of guide pins, a fulcrum pin fixed at the other end thereofwhich is placeable in a selected one of the apertures of the patternchanging member, and means located at a central portion thereof forholding a marking means in contact with the sheet of paper.

Other objects and features of the present invention will be set forth orapparent in the following description and claim and illustrated in theaccompanying drawings, which disclose by way of example and not by Wayof limitation, in a limited number of embodiments, the principal of the3 ,298,104 Patented Jan. 17, 1967 invention and structuralimplementations of the inventive concept.

In the drawings, in which like reference numbers designate likecomponents in the several views:

FIG. l is a plan view of a geometric scribing machine according to theinvention;

FIG. 2 is an elevation view of the geometric scribing machine shown inFIG. l;

FIG. 3 is an end View of the geometric scribing machine shown in FIG. 1;

FIG. 4 is a sectional view of the geometric scribing machine taken alongline 4-4 of FIG. l; and

FIG. 5 is a sectional view of the base member and rotatable table of thegeometric scribing machine shown in FIG. l along line 5-5.

As shown in FIG. l, a geometric scribing machine comprises ve maincomponents: a base member 6, a rotatable table 7, a hand turnable member9 which drives the rotatable table 7 and a pattern adjusting rotatablemember 8 driven by the rotatable table 7.

As best showh in FIG. 4, the pattern adjustable member 8 has xed to it ajournal or shaft member 21 at its center of rotation which cooperateswith a bearing member 22 xed to the base 6. In a similar manner, thetable 7 is rotatably carried by on base member 6 by 21 and 22 as shownin FIG. 5. Also, the hand turnable member 9 is rotatably carried a shaft21 xed thereto and a bearing member (not shown but similar to 22 and22') cooperating therewith and hxed to the base member 6. Alternatively,the shaft members 21, 21 and 21" can be cast integrally with itsassociated rotatable member 8, 7 0r `9 and the bearings rotatablysupporting them, such as 22 and 22', can be simple apertures in the basemember 6.

Rotatable member 9 has extending perpendicularly therefrom at a selecteddistance from its journal 21'l a crank pin 10 which is linger engageableby the operator to rotate member 9.

The hand turnable member 9 and the rotatable table 7 have integraltherewith intermeshing gear teeth 25 and 26 located at selected radiifrom 21' and 21', respectively. Pattern adjustable member 8 has gearteeth 27 integral therewith which intermesh with the gear teeth 2-6 ofthe rotatable table 7. Accordingly, the hand turnable member 9 drivesthe rotatable table 7 which in turn drives the.

pattern adjusting member 8, members 9 and 7 turning in oppositedirections and members 7 and 8 turning in opposite directions. It isimportant to note that the three members 7, 8 and 9 do not all turn inthe same direction and vthat no slippage can occur between such threemembers as would be the case if the three members were driven by a beltmember (which incidentally would drive the three members in the samedirection in direct contradiction to the concept of the presentinvention).

Pattern changing rotatable member 8 has a first plurality of apertures11 along one radial line, a second plurality of apertures 11 alonganother radial line, and still another plurality of apertures 11" along-a third radial line. Such radial lines need not be three in number andmay be, but not necessarily, spaced at intervals when three radial linesare employed. While the plurality of apertures 11, 11 and 11" in each ofthe three radial lines may all be spaced by a common distance, theinnermost aperture of each of the groups 11, 11' and 11" are spaced atdifferent distances from the center of rotation of shaft 21.Accordingly, for the arrangement of apertures 11, 11 and 11" shown inFIG. 1, a fulcrum pin 14 can be placed at any one of 21 different radiirelative to the -center of rotation of member 8.

The fulcrum pin 14 is fixed to one end 13 of a marker carrying bar 12having an elongated slot 17 at the other end thereof. Base member 6 hasa shoulder portion 15 extending therefrom into which are fixed aplurality of guide pins 16 spaced along a curve. Preferably, the pins 16are equally spaced along the arc of a circle. Any one of the guide pins16 can be selected to engage and slide along the inside surfaces of slot17 While the fulcrum pin 14 is selectively positioned in one of theholes 11, 11 and 11". At a medial portion of bar member 12, there isprovided a means to lhold and secure a marking pencil 18 or othermarking devices such as a pen, stylus, etc., and advantageously, suchholding means can be an aperture 19 having a diameter which is slightlysmaller than the maximum diameter of the marker 18.

Centrally, with respect to the shaft 21', there is provided arectangular recess 28 in the rotatable table 7 for receiving arectangular sheet of paper (not shown). So as to lhold down the fourcorners of the rectangular piece of paper, a portion 20 of the rotatabletable 7 extends in the four corners of the recess 28 and spaced atselected distance from the bottom wall 28 of the recess 28 so as toreceive and hold down the four corners of the rectangular sheet ofpaper.

The parameters of the marker 18, the shoulder 15, the fulcrum pin 14 andthe pattern adjusting member 8 are selected so that the end of themarker 18 rests slightly but reliably upon t-he top surface of a sheetof paper placed in recess 28 and secured by corner members 20.

A tremendous variety of patterns will be scribed or traced out by themarker 18 when crank pin 10 is turned in dependence upon: (a) which ofthe 21 apertures 11, 11 and 11 that Aare chosen to engage the fulcrumpin 14 and (b) which of the guide pins 16 selected to engage the sidesof longitudinal slot 17. Two choices of (a) and (b) are shown in FIG. l.

Advantageously, the entire device can be made of only ve parts, each ofwhich can be readily molded of common plastics materials. One integralcomponent can be members 6, and 16, member 6 having aperture to receiveshafts 21, 21 and 21". Another integral component can be members 9, 10,21" and 25. A third integral member can be members 8 with holes 11, 11and 11, 21 and 27. A fourth integral member can be members 7, 20, 21',26 and 28. The remaining fifth integral member can be members 12, 13,14, 17 and 19.

While there has been described and pointed out the fundamental novelfeatures of the invention as applied to preferred embodiments, it willbe understood that various omissions and substitutions and changes inthe form and details of the devices illustrated and its operation may bemade by those skilled in the art, without departing from the spirit oflthe invention. It is the intention, therefore, to be limited only asindicated by the scope of the following claim.

What I claim is:

A geometric scribing machine which comprises a base member; a rotatabletable having gear teeth integral therewith along its periphery andpivoted to said `base member, said rotatable table having a recess in acentral portion thereof adapted to receive a rectangular sheet of paper;means for turning said table; a single pattern changing member pivotedto said base member and having gear teeth integral therewith whichintermesh with the gear teeth on said rotatable table; said singlepattern changing member having a plurality of radially spaced aperturesalong a plurality of discreet straight radial lines wherein all adjacentapertures along each radial line are spaced by a common distance andwherein the innermost aperture of each radial line is spaced differentlyfrom the center of rotation of said pattern changing member; a singleelongated member having a pin-like protrusion at one end thereof whichis placeable in a selected one of the .apertures of said patternchanging member; means xed to said -base member for slidably and:pivotably supporting t-he other end of said elongated member whereinsaid means for slidably and pivotably supporting the other end of saidelongated member includes a plurality of guide portions extendingupwardly from said base member and spaced from each other along a curve,said elongated member having a slot which is engageable with a selectedone of said guide portions and wherein said rotatable table has aportion which extends into each of the four corners of said recess andspaced from the bottom wall of said recess to receive the four cornersof said rectangular piece of paper; and a marking stylus carried by anintermediate portion of said elongated member which is contactable withsaid sheet of paper said writing stylus is carried on an arm extendingtransversely from the elongated member whereby the weight of saidwriting stylus provides Contact pressure between said writing stylus andsaid sheet of paper; the spacing of all apertures being at differentdistances from the center of rotation of said pattern changing member,whereby the pin-like protrusion at the end of said elongated member canbe positioned at distances from the `center of rotation of said patternchanging member equal in number to the total number of apertures in saidpattern changing member.

References Cited by the Examiner UNITED STATES PATENTS 42,260 4/1864Roberts 40-158 X 859,366 7/1907 Clark 33-27V 1,071,681 9/1913 Allen33-27 1,763,885 6/1930 Fisher 33-27 2,532,537 12/1950 Brown 33-782,583,578 l/1952 Lowndes 33-76 X 2,713,723 7/1955 Anderson 33-782,958,132 11/1960 Hartbauer et al. 33 -27 FOREIGN PATENTS 1,222,873 1/1960 France.

418,554 10/1934 Great Britain. 564,645 10/ 1944 Great Britain.

LEONARD FORMAN, Primary Examiner. H. N. HAROIAN, Assistant Examiner.

